Google Cloud Function Entry Point Example

index.js

/**
 * INIT
 * 
 * Entry point that responds to any HTTP request.
 *
 * @param {!express:Request} req HTTP request context.
 * @param {!express:Response} res HTTP response context.
 */
exports.init = ( request, response ) => {

    /**
     * PROCESS HTTP REQUEST.
     */
    let needBlock       = false;

    const getReqHeader  = (key) => request.get(key);
    const Referer       = getReqHeader('Referrer');
    const user_agent    = getReqHeader('User-Agent');

    const ref_host      = Referer ? new URL(Referer).hostname : '';
    const url           = Referer ? new URL(request.originalUrl, Referer) : '/';
    
    needBlock = ( ref_host === '' || url === '/') ? true : false;
  
    /**
     * REMAINING CODE GOES HERE.
     */
    ...

}